The present invention relates to a magnetic head slider capable of maintaining a stable fly height even with a peripheral speed reduced due to the reduction in diameter of a magnetic disk, and a manufacturing method therefor.
A magnetic disk drive uses a magnetic head slider that flies above a spinning magnetic disk recording medium (magnetic disk), while maintaining a microscopic distance (a flying height) therefrom. The magnetic disk drive is required to make the magnetic head slider fly in a low flying state, in which the magnetic head slider is as close as possible to the magnetic disk, in order to increase storage capacity. To achieve such a stringent requirement for the low flying height, a negative pressure type magnetic head slider is currently used. The negative pressure type magnetic head slider offers outstanding flying stability by making use of negative pressure acting on the slider to attract the slider onto the magnetic disk.
The slider disclosed in Patent Document 1 (Japanese Patent Laid-open No. 2000-260015) is well-known, wherein the slider includes micro-protrusions disposed on an air bearing surface thereof, each being independent of each other on the air bearing surface. The micro-protrusions are intended to allow a magnetic head included in the slider to be proximate to a smooth magnetic disk surface with a gap of substantially zero therebetween. Each of the micro-protrusions has a diameter of about 1 μm or less as measured in a slider traveling direction. The total area of vertices of all micro-protrusions is 0.02 mm2 or less.
The magnetic head slider disclosed in Patent Document 2 (Japanese Patent Laid-open No. 2001-297421) is arranged to keep the flying height substantially uniform throughout the entire magnetic disk surface, reduce variations in the flying height at high altitudes, and let the head slider glide smoothly in contact with the magnetic disk should the slider contact the magnetic disk. To achieve these ends, the magnetic head slider includes a magnetic head mounting surface, a slider rail surface, a slider stepped bearing surface, and a negative-pressure groove. The magnetic head mounting surface forms a first surface disposed proximately to the magnetic disk. The slider rail surface forms a second surface disposed further away from the magnetic disk than the magnetic head mounting surface. The slider stepped bearing surface forms a third surface disposed further away from the magnetic disk than the slider rail surface. The negative-pressure groove forms a fourth surface disposed the farthest away from the magnetic disk.
Conventional magnetic disk drives have had a large housing, allowing a magnetic disk used therewith to have a sufficiently large diameter and thus spin at a sufficiently high speed. This in turn has allowed the magnetic head slider flying above the surface of the magnetic disk to generate a sufficiently large lifting force so as to achieve a stable flying height. In recent years, however, the size of the magnetic disk drive has been progressively reduced because of a trend toward adopting magnetic disk drives in portable devices, and the like. Because the peripheral speed becomes lower for the magnetic disks having smaller diameters, therefore, it is becoming more difficult to achieve a sufficient flying force of the magnetic head slider. Accordingly, a need arises for a magnetic head slider that generates a sufficient lifting force even with a reduced peripheral speed of the magnetic disk and maintains a stable fly height.